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sequences in the basins of Alpine mobile belts should be viewed as a pecu-
liar actively functioning tectonic energy “boiler” defining regional struc-
ture of the overlying complexes. Obviously, the clay sequence itself under
such environment represents maximally unbalanced geosystem of a highly
complex irregular structure, horizontal-vertical (quasi-undulatory) mobil-
ity of the plastic matter, etc.
Another phenomenon that may affect the folding and its magnitude is
the catagenic decompaction of clay due to dehydration of montmorillon-
ite group minerals under elevated temperature. The release of substantial
“regenerated” water amounts from the crystalline grid and inter-package
spaces of these minerals is accompanied by significant increases of the
pore pressure in the sequence, of its volume (up to 20-40%: Blokh, 1969;
Bro, 1980; Kartsev and Vagin, 1973; Fertl, 1980), water-saturation and
plasticity. It may result (only zonally, not regionally) in corrugation of the
incompetent interval's surface, in the formation of zones (areas) of crushed
(“twisted”) clay, of isoclinal structure with fine secondary and tertiary fold-
ing. This phenomenon deserves additional studies.
The reviewed cases are just an instant shot of numerous factors con-
trolling the formation and spatial development of similar folds, faults, etc.
under other geologic environments. It is reasonable, however, to assume
that in the specific situation of Alpine basins the geodynamic mecha-
nisms associated with geo-fluid-dynamic processes (realization of elasto-
plastic properties embedded in thick Paleogene-Miocene clay sequences)
dominate.
In a more general case, it probably would be legitimate to state that one
of important factors in the formation of this type folding in the mobile
belt regions is the AHPP manifestations in the regional geo-fluid-dynamic
processes.
5.2 RegionalDynamicsof Ground Waters
The issue of hydrodynamics in deep stratospheric horizons is controversial
and has no single solution. Different views of the issue include infiltration,
elision, injection/cross-flow, etc.
Geologic publications commonly treat the movement of ground water
and hydrocarbons as a subordinated issue together with oil and gas forma-
tion. The solution of this problem should be an integrated one based on
as much actual data as possible, including tectonic, lithofacies, geobaric,
geotermal, petroleum geologic, etc.
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